The actress, who is best known for her role as Hermoine in the "Harry Potter" series, plays Noah's adopted daughter Ila in next month's release. The British actress was forced to film most of her scenes with Douglas Booth, who plays Shem, early in the morning between 4 a.m. and 7 a.m.

"Because the film has a pro-environment message, Darren didn't want anyone drinking from plastic water bottles on set either. So that made things slightly harder," said Watson.

Because of the grueling schedule, Watson admitted that at times she struggled to be fully aware of her surroundings.

"Everything we used had to be recycled or recyclable. Having no water bottles on set at five in the morning, when you're exhausted and delirious, wasn't ideal. I was so tired one morning I picked up a mug from my trailer and drank some stagnant water that had been there for the duration – so three months. I was so ill," she said.

Hoping for a sympathetic response from Aronofsky, Watson said the director informed her she should "use" her sickness in her work.

"I came in the next day and was like: 'Darren, I don't think I can do this, I'm really sick,'" she said. "He was like: 'Use it for the scene.' And I turned round to the bus and was like: 'Is he joking? He is joking right?' and there was deadly silence."

Watson's illness was not the only hiccup that "Noah" faced. While much of the film relies on special effects, the film was nevertheless hampered by physical problems after Hurricane Sandy shutdown filming for several weeks, obstructing the film crew's access to the ark, which was being held in Oyster Bay, an inlet on the Long Island Sound, and a location that fell directly in the storm's path.

Additionally, after the film superseded its initial $125 million budget and became the costliest movie that Aronofsky has ever made, Paramount Pictures forced the director to show several different versions of the unfinished movie to test audiences last year.

Early feedback from religious audiences suggested that they were not completely on board with the director's depiction of Noah, questioning "the film's adherence to the Bible story and reacted negatively to the intensity and darkness of the lead character" after he got drunk and considered "taking drastic measures to eradicate mankind from the planet."